This study will determine whether the initial use of two nucleoside reverse transcriptase inhibitors (NRTIs) and nelfinavir followed by two different NRTIs plus efavirenz is superior to initial use of 2 NRTIs plus efavirenz followed by two different two NRTIs and nelfinavir. This study will also include pharmacokinetic, immunologic, and metabolic components. The GCRC will be used for pharmacokinetic and metabolic studies.